import java.util.Scanner;
public class xio {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入一个字符串：");
        //键盘录入一个字符串
        String str = sc.next();
        //将字符串反转
        String sb = new StringBuilder().append(str).reverse().toString();
        //判断是否是回文串
        if (sb.equals(str)) {
            System.out.println("是回文串");
        }else {
            System.out.println("不是回文串");
        }


    }
}
